US Bridges

12th Ave over Cedar River & RD

Fair

Linn County, Iowa · 083072812 · Structure no. 000000000501030

Built
1974
51 years old
Condition
Fair
inspected July 2024
Type
Arch - Deck
Concrete Continuous
Length
800 ft
5 main spans
Daily traffic
5,228
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

12th Ave over Cedar River & RD is a concrete continuous arch - deck carrying 12th Ave over Cedar River & RD in Linn County, Iowa. It was built in 1974, so it is 51 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 5,228 vehicles a day, projected to reach 5,228 by 2044. The structure is 800 ft (243.8 m) long and 71 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
Carries12th Ave
CrossesCedar River & RD
Location083072812
RouteCity Street 0
CountyLinn County
StateIowa
Coordinates41.96708, -91.66211
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating66.9 US tons
Inventory rating40.1 US tons

Structure

Structure typeArch - Deck
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length800 ft (243.8 m)
Longest span160 ft (48.8 m)
Deck width71 ft (21.5 m)
Roadway width54 ft (16.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,228 (2022)
Projected traffic5,228 by 2044
Trucks0%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway and waterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 12th Ave over Cedar River & RD built?

It was built in 1974, making it 51 years old in 2025.

What condition is 12th Ave over Cedar River & RD in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in July 2024.

How much traffic does 12th Ave over Cedar River & RD carry?

About 5,228 vehicles per day (2022 count).

How long is 12th Ave over Cedar River & RD?

The structure is 800 ft (243.8 m) long with a longest span of 160 ft (48.8 m) and a deck 71 ft wide.

Who owns 12th Ave over Cedar River & RD?

It is owned by the City or Municipal Highway Agency.